We plan to investigate the incidence and effects of secretion by neoplasms of two recently identified vasoactive polypeptides: the vasoactive intestinal polypeptide (VIP), and a related vasoactive lung polypeptide. These peptides will be detected and measured by radioimmunoassay of plasma and tissues from normal (experimental animals, human subjects) and neoplastic lesions (human subjects), and by immunofluorescent staining of tissues. The findings will be analyzed for the possibilities of: use of the peptides as markers for the presence of certain neoplasms, and their significance as mediators of paraneoplastic syndromes, especially "pancreatic cholera", flushing and hypercalcemia.